Questions about the positions of Tech Sgt. and Sgt. Major in WWII?

My grandfather served in WWII and i had a few questions about what his role was.

He was a marine corps combat correspondent in WWII

"I spent nearly two years in the Pacific theater-taking part in amphibious landings and combat aerial missions. What I was discharged at the Washington, DC, Naval Yard, September 1945, I was a Tech Sgt. - five stripes- and was offered a promition to Sgt. Major-a six striper- if I chose to remain in the Corps. My reply was thanks, but no thanks." - from a letter he wrote to me

So my questions are:

What were his duties as a Tech Sgt?

Would that be a very good rank for a noncom?

Would Sgt. Major be a notable rank?

Any other information along these lines would be very helpful

Thanks, Chris

Questions about the positions of Tech Sgt. and Sgt. Major in WWII?symphony

Tech Sgts didn't hold line (command) authority, they received a higher pay grade based on special skills but did not have men that they were responsible for. After WWII there was an entire line of "specialists" replacing the "tech" position, that held higher grades based on their technical skills, but now the only grade of this sort that remains is the single specialist grade. My dad was in the Army during the Korean War, he was proud that he was a Corporal, rather than what he described as a "Chicken Corporal" - the specialist at the same grade as corporal (the specialist patches looked like upside-down non-specialist patches with an eagle in the middle). Tech Sgts insignias in WWII had a "T" between the chevrons and the rockers.

Sgt. Major is a very notable pay grade, it is the most senior enlist grade and considered to be a very high honor.